Process of preserving egg.



UNITED STATES PATENT OFFICE.

SIMEON c. KEITH, JR, or BROOKLINE, MASSACHUSETTS, Assrenoa To B. .r. KEITH COMPANY, 013 BOSTON, MASSACHUSE TS, A CORPORATION OF MASSACHUSETTS.

PROCESS OF PRESERVING EGG.

No Drawing.

Specification of Letters Patent.

Application filed January 2, 1914. Serial No. 809,867.

Patented Sept. 29, 1914.

to the preserwhites and yolks respectively. It has been the practice in such case to make a batter to roduce a uniform mixture and then to sub ect the mixture to a relatively low temperature for the purpose of freezlng, and holding it at a temperature where the aptivity of micro-organisms ceases. This product, however, has not been wholly satisfactory for the reason that there 1s a tendency of the constituents of the matter be-' ing frozen to separate, according to the varying specific gravities of the const1tuents or component portions of the mixture. For instance, in egg mixtures there is a natural tendency of the yolk to accumulate in the upper portion of the mass and for the whites so-called to accumulate in the lower portion. The result of all this is that, when the mixture is finally frozen to asubstantially solid condition, the mass is not uniform throughout the can or container. Furthermore care must be taken in following the old process to prevent too rapid freezing of the mixture, as otherwise it frequently happens that the cans or containers are burst by the swelling of the frozen mass from expansion due to freezing. On the other hand, where the temperature of the mass being treated is slowly reduced, there is a greater length of time permitted for the changes to take place, due to bacterial action and the oxidation of the fatty constituents.

For the purpose of overcoming the -objections to the process which I have herein referred to, the present invention consists of a process in which the substance to be preserved is subjected to a constant stirring or churning action while being frozen so as to preserve the equality of the mixture. This may be accomplished by means of an ordinary freezing apparatus such as is used There are on the market at the present time var ous machines for this purpose, some of which are continuous in their operation, the cream or mixture being supplied and the inthe manufacture of ice cream so-called,

frozen. mass being fed away from the ma-- chine continuously. By thus agitating the product while it is being frozen,there is secured a uniform mixture or magma. Ordinarily, of course when a batter or mixture of that sort is frozen by an ice cream freezer, there is incorporated in the mixture or magma a large amount of air. The presence of the air does not ordinarily injure ice or other products which are to be used immediately, but, in the products which are to be 4 preserved for any length of time, the air contained 111 the mixture or magma tends to bring about an oxidation of the fats with a consequent deterioration of the product.

presence of the air greatly Furthermore the increases the bulk of the product and necessltates the use of larger containers.- than would otherwise be needed and greatly increases the cost of carrying on the business because of the increased storage charges and the increased cost of the cans or containers. My invention, therefore, consists further in the removal or exclusion of the air from the product while it is being frozen. This s accomplished by subjecting the product during the freezing to a vacuum, or, in other Words, in carrying on the freezing operation in vacuo. As a result, the expansion of the mixture or magma when frozen is limited to the expansion due to crystallization of some of the aqueous portions of the product. After the product has been frozen in oac'zm, it may be placed in cans or containers of relatively smaller size than would otherwise be employed, and may be kept for relatively long periods without danger of deterioration due to oxidation and without any material change in flavor.

Preferably the temperature of the product is brought during the freezing operation to approximately 25 to 27 F. After the product has been thus thoroughly agitated and partially frozen in vacuo, and has been placed in cans or containers, the latter are held in a refrigerator and are reduced to a temperature of substantially zero degrees F., at which temperature they are maintained until ready for use.

I have not deemed it necessary to show any apparatus for agitating and prelimi narily freezing the product in arrow, as many of the standard machines which are at the present time used for freezing ice cream may be utilized for this purpose, the

only change necessary in such machines being *eithertooperate them in a vacuum chamber, or else to seal the compartment 1n which the product to be frozen is contained A mass of egg batter, either whole or separated eggs, ,on being agitated and frozen in cacao, and then further frozen to a temperature of approximately zero degrees F., is substantially solid and contains substantially no air. As a result of the initial freezing, the magma is mushy and is, not swollen more than is due to the crystallization of the water, differing in this respect from the ordinary ice cream, the bulk of which is increased by the air in the mixture. I secure by my process a new product or article of manufacture, to wit, a frozen homogeneous compact mass of egg containing no air. By the employment of the term homogeneous I mean a mass which is substantially of the same consistency, and in which the constituents or component parts are distributed equally throughout the mass. This product is marketed in closed cans or containers and is kept frozen until ready for use.

What I claim is:

1. As a new product or article of manufacture, a churned homogeneous solid frozen egg mixture containing substantially no air.

2. The herein described process which consists in agitating or churning an e g mixture in 'vacuo and simultaneously freezing such mixture.

3. The herein described process which consists inagitating or churning an egg mixture in vacuo and simultaneously freezing such mixture, and then freezing and holding such mixture at a temperature of approximately zero degrees F. 1

In testimony whereof I have aflixed my signature, in presence of two witnesses.

SIMEON C. KEITH, JR. Witnesses:

P. W. PEzzE'r'rI, E. P. BR UNEN. 

